The construction and installation of prefabricated panels in the roof and sidewall areas of building construction has been the object of much design effort, and a number of different designs have been commercially successful to varying degrees. The present invention relates to structures of the type wherein panels are preformed of sheet metal or other strong sheet material and are provided with longitudinal ribbing which forms a part of the retaining means for securing the panels to the building frame structure, such panels often being referred to as "standing seam" panels.
Building panels so designed as to be held entirely from beneath by fastening means which require no apertures in the panels and which provide a leakproof structure under the severe conditions encountered in roofing applications have been designed with standing seams which are deformed during installation of the panels to interlock the edges of adjacent panels and simultaneously interlock the seamed areas with underlying fastener clips preattached to the framing elements of the building. Although a number of such systems achieve satisfactory performance, many of them require that each workman be equipped with a heavy and expensive seam crimping machine which he must often manipulate on a roof under difficult conditions. The seaming machines are also typically slow, and involve dealing with an electrical supply cord. The design of the preformed seamable contours in the panels also frequently prevents efficient nesting of the panels for shipment. It will be appreciated that these disadvantageous factors have the net effect of adding to the cost of the finished structure.
Where seaming machines are used they also usually leave marks on the seams, which is of course undesireable when the panels are to be installed in areas which are readily visible, as in wall construction.
Preformed seam portions have also been used which are designed to be pounded together and onto underlying holding clips in the field by means of a rubber mallet. Due to the small size of such pounded seams, however, it is difficult to insure that they are fully interlocked, leakproof, and capable of withstanding the high lift off forces created by winds. Also, durinf installation almost all known panel designs present location or positioning problems in that a significant amount of time may be required to make sure that the anchoring means are properly spaced and/or that all through fasteners in fact pass through the supporting structure. Many prior standing seam designs also require a separate cap element. The present invention eliminates such problems and requires no cap.
With the foregoing in mind, it is the overall object of the present invention to provide an improved panel construction of the indicated character so designed that the panels can be secured to the attaching means which secures them to the frame structure merely by pressing the panels into place, which provides a panel structure which is very strong and highly resistant to the uplifting forces which are sometimes developed as a result of wind, yet which is effectively sealed and weathertight.
An object related to that stated is to provide such a panel construction which is not only low in first cost, but which incorporates improved prelocating and positioning means which makes the system inexpensive and quick to install. In roofing operations in accordance with this invention, the workmen can install the locating and fastening means for each successive panel, and the panel itself, while safely standing or kneeling on the preceding panel. Speed of installation and economy as well as safety, reliability and efficiency are also augmented by the fact that this invention permits the use of wider panels than can be employed with most prior systems, without sacrifice of strength or resistance to lift off, and by the fact that expansion and contraction of the panels due to temperature changes is accommodated by sliding of the panels relatively to the clips without generating harmful stresses.
Other objects and advantages will become apparent to persons skilled in the art upon consideration of the present disclosures in its entirety.